Boarder's toxic levels stun pathologist

One of six people who died at a Sydney boarding house over a 14-month period had toxic levels of an antipsychotic drug in her system, an inquest has heard.

Shaneen Batts, 60, was found dead in her room in June 2009, with a post-mortem examination determining she had toxic levels of the drug Olanzapine in her system.

Ms Batts was one of six residents at 300 Livingstone Road, Marrickville, who died between 2009 and 2010.

The inquest is examining the circumstances of her death along with the deaths of Ilona Takacs, Dorothy Hudson, Ian Birks, Donald MacKellar and Mohammed Ramzan.

Chief forensic pathologist at the Department of Forensic Medicine, Dr Johan Duflou, told the court he was surprised when he discovered the high levels of Olanzapine had most likely caused Ms Batts' death.